The present invention relates to a technique for supplying directly the fuel into a combustion chamber of an internal combustion engine and particularly to a fuel injection method of a direct injection type internal combustion engine, a fuel injector of a direct injection type internal combustion engine, a direct injection type internal combustion engine, and a combustion method of a direct injection type internal combustion engine.
To improve of a fuel consumption, a stratification lean burn is an important combustion method. To realize the stratification lean burn, it is necessary to gather a rich air-fuel mixture at a vicinity of an ignition plug and a technique relating the about technique shown in, for example, is Japanese application patent laid-open publication No. Hei 6-81651 and Japanese application patent laid-open publication No. Hei 6-81656 has known.
In a technique shown in the above stated Japanese application patent laid-open publication No. Hei 6-81651, a tumble is formed in a cylinder and an injected fuel is collided with a piston and the fuel is guided according to a wall of a cavity and is supported according to the tumble and then the fuel is supplied to an ignition plug.
Further, to form an atomization of the fuel spray it is effective to employ a tumble system fuel injector and the fuel spray during this case is become a hollow conical shape. FIG. 3 shows a prior art to which the above stated technique according to the prior art is combined.
Further, in a technique shown in the above stated Japanese application patent laid-open publication No. Hei 6-81656, a tumble is formed in a cylinder and from a first injection port of a fuel injector the fuel is injected in a direction of an ignition plug and from a second injection port of the fuel injector the fuel is injected in a direction which is along to a flow of the tumble (through an immediately below portion of an air intake valve and aiming to a vicinity immediately below portion of an air exhaust valve and to a slight squint direction against to a horizontal direction of the cylinder), namely the fuel is injected to two directions.
In the above stated conventional fuel injection techniques, it is not taken the consideration about a fuel adhesion to the piston, the wall face of the cylinder or the ignition plug, since the fuel adhesion to the piston is caused, it is not preferable to reduce a discharge HC (a non-combustible hydrocarbon (HC)) according to an incomplete combustion of the adhesion fuel.
The present invention is devised from the above stated problems and to solve these problems.
An object of the present invention is to provide a fuel injection method of a direct injection type internal combustion engine, a fuel injector of a direct injection type internal combustion engine, a direct injection type internal combustion engine, and a combustion method of a direct injection type internal combustion engine wherein a fuel adhesion amount to the piston can be reduced.
Another object of the present invention is to provide a fuel injection method of a direct injection type internal combustion engine, a fuel injector of a direct injection type internal combustion engine, a direct injection type internal combustion engine, and a combustion method of a direct injection type internal combustion engine wherein a discharge HC can be reduced.
A further object of the present invention is to provide a fuel injection method of a direct injection type internal combustion engine, a fuel injector of a direct injection type internal combustion engine, a direct injection type internal combustion engine, and a combustion method of a direct injection type internal combustion engine wherein a fuel consumption can be improved.
A further more object of the present invention is to provide a fuel injection method of a direct injection type internal combustion engine, a fuel injector of a direct injection type internal combustion engine, a direct injection type internal combustion engine, and a combustion method of a direct injection type internal combustion engine wherein a combustion stability performance can be improved.
A further more object of the present invention is to provide a fuel injection method of a direct injection type internal combustion engine, a fuel injector of a direct injection type internal combustion engine, a direct injection type internal combustion engine, and a combustion method of a direct injection type internal combustion engine wherein a formation of a stratification at the high rotation area can be attained.
To attain the above stated objects, according to the present invention, a fuel injection method of a direct injection type internal combustion engine comprises of the steps of changing a volume of a combustion chamber according to a piston, generating a tumble flow of air in said combustion chamber, dividing a fuel spray into a fuel spray having a strong penetration force and a fuel spray having a small penetration force, and injecting directly the fuel in said combustion chamber to direct said fuel spray having said strong penetration force in a direction of an ignition plug and to direct said fuel spray having said small penetration force in a direction of said piston.
To attain the above stated objects, according to the present invention, a direct injection type fuel injector comprises a fuel passage having a fuel injection port at an end portion, a valve seat provided in a midway of said fuel passage, a valve body for opening and closing said fuel passage by incorporating with said valve seat, a tumble element for giving a tumble force to fuel which passes through between said valve body and said valve seat, and a fuel spray division means having a splitter which is provided on said fuel injection port at a position which is eccentrically from a center of said fuel injection port.
To attain the above stated objects, according to the present invention, a direct injection type fuel injector comprises a fuel passage having a fuel injection port at an end portion, a valve seat provided in a midway of said fuel passage, a valve body for opening and closing said fuel passage by incorporating with said valve seat, a tumble element for giving a tumble force to fuel which passes through between said valve body and said valve seat, a fuel spray division means having a splitter which is provided on said fuel injection port, a portion for opposing said fuel injector port of said splitter is formed with a mountain shape having unequal sides.
To attain the above stated objects, according to the present invention, a direct injection type fuel injector comprises a fuel passage having a fuel injection port at an end portion, a valve seat provided in a midway of said fuel passage, a valve body for opening and closing said fuel passage by incorporating with said valve seat, a fuel enlargement means provided on said fuel injection port and having a hole having a diameter larger than a diameter of said fuel injection port, a fuel guidance means provided on a downstream of said fuel enlargement means and having a slit like hole, a fuel spray means provided at a downstream of said fuel guidance means and having a first slit like hole provided at a rectangular direction against to said slit like hole of said fuel guidance means and a second slit like hole in parallel to said first slit like hole and having a width larger than a width of said first slit like hole.
To attain the above stated objects, according to the present invention, a direct injection type internal combustion engine comprises a combustion chamber for inhaling air through an air intake valve, a piston for varying a volume of said combustion chamber, a tumble flow generation means for generating a tumble flow of the air in said combustion chamber, and a fuel injector being a direct injection type fuel injector for supplying directly a fuel into said combustion chamber and for injecting the fuel by dividing into a first fuel spray having a strong penetration force and a second fuel spray having a small penetration force, said fuel injector is arranged against to said combustion chamber to inject said first fuel spray having said strong penetration force which is injected from said fuel injector in a direction of an ignition plug and to inject said second fuel spray having said small penetration force in a direction of said piston, and according to said tumble flow of the air said first fuel spray having said strong penetration force is guided to a side of said ignition plug.
To attain the above stated objects, according to the present invention, a direct injection type internal combustion engine comprises a combustion chamber for inhaling air through two air intake valves, a piston for varying a volume of said combustion chamber, a tumble flow generation means for generating a tumble flow of the air in said combustion chamber, and a fuel injector provided between said two air intake valves and for supplying directly a fuel to said combustion chamber where said tumble flow of the air is generated, a fuel spray to be injected is divided into a first fuel spray having a strong penetration force and a second fuel spray having a small penetration force, and said first fuel spray having said strong penetration force is injected to a direction of an ignition plug or a vicinity of said ignition plug and said second fuel spray having said small penetration force is injected to a direction of said piston.
To attain the above stated objects, according to the present invention, a fuel combustion method of a direct injection type internal combustion comprises of the steps of: varying a volume of a combustion chamber according to a piston, generating a forward tumble air flow in said combustion chamber, injecting divided a first fuel spray injected to a direction of an ignition plug or a vicinity of said ignition plug and having a strong penetration force and a second fuel spray injected to a direction of said piston and having a small penetration force, by winding up said second fuel spray having the small penetration force from said direction of said piston according to said forward tumble air flow and transporting said second fuel spray having the small penetration force to said direction of said ignition plug, and burning said fuel spray by igniting said ignition plug.
When the fuel spray is observed from a side of the combustion chamber, the spread angle of the fuel spray having the strong penetration force to the peripheral wall of the cylinder is smaller than the spread angle of the fuel spray having the small penetration force to the peripheral wall of the cylinder. As a result, the fuel having the necessary amount can be dispersed at the specific area in the cylinder and without of the lowering of the spark performance, it is possible to carry out the super lean burn operation.